Enciphering Apparatus and Method, Deciphering Apparatus and Method as Well as Information Processing Apparatus and Method

1. An electronic device for enciphering data using a cryptographic key, comprising: an operation section operated by a user to output a signal corresponding to an operation selected by the user; non-volatile memory means for storing information; first providing means for providing first information; second providing means for providing second information which is changed during a session; producing means for producing a cryptographic key based on the first information and the second information; enciphering means for enciphering data using said cryptographic key, wherein said cryptographic key is changed at a predetermined timing during the session in accordance with a change in said second information; and transmission means for transmitting the enciphered data to another electronic device.

2. The device of claim 1 , further comprising a disk drive for reproducing data recorded on a disk.

3. The device of claim 2 , wherein said disk drive is a DVD drive.

4. The device of claim 2 , wherein said disk drive records data onto the disk.

5. The device of claim 1 , wherein said operation section is a button, a switch or a remote controller.

6. An electronics device for deciphering data using a cryptographic key, comprising: an operation section operated by a user to output a signal corresponding to an operation selected by the user; non-volatile memory means for storing information; receiving means for receiving enciphered data from another electronics device; first providing means for providing first information; second providing means for providing second information which is changed during a session; producing means for producing a cryptographic key based upon the first information and the second information; and deciphering means for deciphering said received enciphered data using said cryptographic key, wherein said cryptographic key is changed at a predetermined timing during the session in accordance with a change in said second information.

7. The device of claim 6 , further comprising a disk drive for reproducing data recorded on a disk.

8. The device of claim 7 , wherein said disk drive is a DVD drive.

9. The device of claim 7 , wherein said disk drive records data onto the disk.

10. The device of claim 6 , wherein said operation section is a button, a switch or a remote controller.

11. An electronics device for enciphering data using a cryptographic key, comprising: an operation section operated by a user to output a signal corresponding to an operation selected by the user; non-volatile memory means for storing information; an encipherer; a first information provider; a second information provider; a cryptographic key producer coupled with said encipherer, whereby said encipherer enciphers data using a cryptographic key produced by said cryptographic key producer based upon first information provided by said first information provider and second information provided by said second information provider and changed at a predetermined timing during a session; and transmission means for transmitting the enciphered data to another electronic device.

12. The device of claim 11 , further comprising a disk drive for reproducing data recorded on a disk.

13. The device of claim 12 , wherein said disk drive is a DVD drive.

14. The device of claim 12 , wherein said disk drive records data onto the disk.

15. The device of claim 11 , wherein said operation section is a button, a switch or a remote controller.

16. An electronics device for enciphering data using a cryptographic key, comprising: an operation section operated by a user to output a signal corresponding to an operation selected by the user; non-volatile memory means for storing information; first providing means for providing first information which is held in common with a processing device in an authentication process by communication between the two devices; second providing means for providing second information which is changed at a predetermined timing; producing means for producing the cryptographic key based on the first information held in common with the processing device and the second information which is used for changing the cryptographic key; enciphering means for enciphering data using said cryptographic key, wherein said cryptographic key is changed at a predetermined timing in accordance with a change in said second information; and transmission means for transmitting the enciphered data to another electronic device.

17. The device of claim 16 , further comprising a disk drive for reproducing data recorded on a disk.

18. The device of claim 17 , wherein said disk drive is a DVD drive.

19. The device of claim 17 , wherein said disk drive records data onto the disk.

20. The device of claim 16 , wherein said operation section is a button, a switch or a remote controller.

21. An electronics device for enciphering data using a cryptographic key, comprising: an operation section operated by a user to output a signal corresponding to an operation selected by the user; non-volatile memory means for storing information; an encipherer; a first information provider; a second information provider; a cryptographic key producer coupled with said encipherer, whereby said encipherer enciphers data using a cryptographic key produced by said cryptographic key producer based upon first information provided by said first information provider and held in common with a processing device in an authentication process by communication between the two devices, and second information provided by said second information provider and changed at a predetermined timing; and transmission means for transmitting the enciphered data to another electronic device.

22. The device of claim 21 , further comprising a disk drive for reproducing data recorded on a disk.

23. The device of claim 22 , wherein said disk drive is a DVD drive.

24. The device of claim 22 , wherein said disk drive records data onto the disk.

25. The device of claim 21 , wherein said operation section is a button, a switch or a remote controller.